Boring head for continuous mining machine



Aug. 16, 1955 .1. s. ROBBINS BORING HEAD FOR CONTINUOUS MINING MACHINE 2 Sheets-Sheet 1 S .m Rb m m m m3 S e m a J bm Y B VV W- ATTORNEY Filed June 1, 1954 Aug. 16, 1955 J. 5. ROBBINS BORING HEAD FOR CONTINUOUS MINING MACHINE Filed June 1, 1954 2 Sheets-Sheet 2 f INVENTOR. James 3. Robbins A T TORNE Y Patented Aug. 16, 1955 BORING HEAD FOR CONTINUOUS MINING MACHINE James S. Robbins, Chicago, Ill., assignor to Goodman Manufacturing Company, Chicago, 111., a corporation of Illinois Application June 1, 1954, Serial NO. 433,578

2 Claims. (Cl. 262-7) This invention relates to improvements in mining machines of the boring type especially adapted to cut a bore in advance of the machine. A well-known form of such boring machines is provided with a pair of laterally spaced boring heads, each with a plurality of radial arms, adapted to cut contiguous bores in the working face, and also having auxiliary horizontal upper and lower cutter bars disposed immediately behind the boring heads for trimming the circular bore pattern to produce flat roof and floor surfaces.

Boring heads of the kind above mentioned are usually provided with a plurality of forwardly projecting bitcarrying cutter supports mounted in spaced relation along each radial arm of the head, the arms having the same number and spacing of cutter supports so as to produce a limited number of circular kerfs in the working face, and leaving outstanding cores of mineral between adjacent kerfs, to be dislodged in relatively large lumps by suitable breaker devices also carried by the boring head.

In order to provide desired flexibility of boring action of such boring heads, as well as maneuverability of the mining machine under working conditions in the mine, the mining machine usually has one or more cutter heads suitably mounted on an auxiliary frame which is tiltable with the cutter heads both for vertical and horizontal adjustments relative to the mobile base of the machine, as is shown for instance in my prior application, Serial No. 345,157 filed March 27, 1953.

Among the objects of the present invention is to provide an improved form and arrangement of the Outermost cutter support and the cutter bits carried thereby at an outwardly flared angle so as to facilitate the tilting adjustments of he cutter head wih respect to the mining machine during mining operations.

The invention may best be understood by reference to the accompanying drawings, in which:

Figure l is a side view of a mining machine constructed in accordance with my invention,

Figure 2 is an enlarged fragmentary detail section taken generally along the axis of rotation of the boring head; and

Figure 3 is an enlarged end view of one of the radial arms of the boring head showing the disposition of the cutting bits thereon.

Referring now to details of the embodiment of my invention, the same is shown in Figure 1 as applied to a mining machine of the general type disclosed in my application bearing Serial No. 345,157 filed March 27, 1953. The mining machine has as its principal elements a main frame 10, mounted on endless treads 11, and having an auxiliary frame 12 mounted on the main frame for limited longitudinal and lateral tilting adjustments, by a plurality of jacks 13 and 14.

A boring head is indicated generally at 15, mounted as usual for horizontal progression into a working face of a mine. The machine may, as usual, employ two similar boring heads in side by side relation to cut contiguous bores.

Referring to Figure 2, the boring head is suitably mounted on the front end of a drive shaft 16, suitably journalled in the auxiliary or tilting frame 12 as by bearings 17, 18.

The boring head has a hub 20 fixed on shaft 16 and having a plurality of similar radial arms 21, 21, herein three in number.

Each arm 21 includes a hollow generally cylindrical inner arm portion 22 formed integral with the hub and a telescopic end portion 23. Suitable mechanism (not shown) may be mounted as usual in the hub for effecting simultaneous extension or retraction thereof of all the telescopic end portions to change the maximum working diameter of the boring head.

A plurality of cutter supports are mounted on each radial arm 21 and projecting forwardly from the latter, in the form shown herein, two such cutter supports 25 and 26 being carried on the inner arm portion 22 and a third cutter support 27 being carried at the outer end of the telescoping end portion 23. Each of such cutter supports has a cluster of cutter bits 28, suitably arranged as usual in generally arcuate relation along the front edge of each support so as to conform generally with the shape of the circular kerf to be cut by said support. Certain of the cutter supports, as for instance the inner supports 25 and 26 may also have, as usual, outwardly facing wedge or cam surfaces 29 adjacent their bases 30 for dislodging adjacent cores of material left on the working face between the cutter supports.

The cutter supports may be detachably mounted on the arms by suitable fastening means, details of which are omitted as they form no part of the present invention.

Referring now to the novel form and arrangement of the outermost cutter support or bracket 27 on the end of the telescopic end portion 23 of each radial arm, it will be seen in Figures 1 and 2 that this cutter support is widened circumferentially of the head, and extends forwardly for the major part of its length at an angle of several degrees to the axis of rotation of the cutter head. This angle is indicated in Figure l by the dot and dash line 36. Since in the illustrative form of cutter head shown, the radial arms are disposed substantially at right angles to the axis of rotation of said head, the cutter support 27 also extends at an outwardly flaring angle to its radial arm. In particular, the outer face 37 of the cutter support 27 is at a progressively increasing distance from the axis of the cutter head, excepting at the forward end of said support, where it may terminate in a cluster of cutter bit holders 38, 38, of conventional form for securing cutter bits 28, 28 at varying angles to the support, of sufficient width. In the illustrative form shown three such cutter bit holders are arranged on a slight are, as usual, along the front edge of the support to conform generally with the circular kerf to be cut thereby. It will be noted, however, that said cutter bits are disposed to cut a circular kerf of suflicient width to admit their support arm 27 into the Working face, at least for the major part of its length.

In addition to the terminal cutter bits 28 on each cutter support 27, the outer face 37 of each support is provided with a series of outwardly extending cutter bits 40, 40, along the leading edge of said surface. As shown in Figures 2 and 3, four such cutter bits are provided. Any suitable means may be provided for detachable mounting of the bits 40 in the form shown herein, said bits being fitted in sockets formed near the leading edge of the support, and held in place as usual by set screws 41, introduced from the outer edge of said support.

The adjacent outer end surface 42 of the radial arm is preferably inclined at the same flared angle as the outer face 37 of the cutter bit support, as shown in Figure 2 'One or more cutter bits 43, similar to the bits 40, may also be mounted along the leading side of said end surface 42, as shown in detail in Figure 3.

I will n w be unde stood that the form n m ng ment of u ter bi ieuppo t above dese ihed W llp lm the cu er head to be tilt in any d re tion wh le nt ing, as for instance for following up and down seams, without bjection ble bin ing of he t er head in h 'rb rer It may be explained in this connection, that resistance to deviation from forward boring progress of the head when t the latter is working in a mine face is especially eritical wi h resp c to the o t rm st o t Shep-on 27, eine their outer faces are surr nded by solid n el, whereas 7 he n rm die eeut e s ppor 25 and 26 a e only surnd d by r latively t n standing oree of mat rial which ean be re dily roken, For t is rea n, th flared arrangement may usually be applied 'onl-yto'the outer mo t n ter supp r as here n bo e hown and describ f' 7 When he utter h 'irom its nll'linepeeit qn to do ted line position indi ate in Figu e i wi l be obe i ed hat he out r d'of th radial rni ean it wayi t n lar po it n, by meaneo fe t r' a bits 28, 0 and 3 on th out eee o upper d e d a e 2 o the mnperti nlan it l be n d tha the u rd h re o h Su t is ene iiothetit' will normally cut i s way torwar 't eel ef subs antial clearance between its rear end and th bQ Q1batif v thehead is initially tilted to a relatively slight angle e r e d d es n t m d a y h el ga n t thehore! Instead, the angular clearance is such as to permit the head to be tilted as the boring operation proceeda with.

a minimum amo nt of ut ing by the ent r bite on under face ofv the cutter. support until the new boring,

angle. is established. 7 l v t 7 Although I have shown and described a preferred form ofrmy invention, it should be =understood' that the dist p one e llyexte di g er v a the en thereof means capable of cutting annular lgerf in a mine face 7 when said boring arm assembly is rotated thereagainst, said bracket flaring outwardly forwardly and having cutter bit means extending along at least the outer sur: face thereof whereby said boring arm assembly can be pi oted UP 0; down while ut ng to f llow ar ions in l el of e seeme 2-111; 3 nement mee in for rem ving mine om a so id s am e m bile base, a en t ng and dislo 2 h a mounted n S id ba fornp an down i i 'al ii o em nt with eepe'e there o e d nt in and iielod ingth ed i cluding .at le s on bori g a m e eetnle ebo t'a ho izon al axi and aving a eeet a" forwardly extending bracket terminating in cutter bit meene ep ble of ntt ng.en annu ar er in a mine iae' when saitibo ng 'ermas emb y ro h ee ei st, aid ra ket having a reat r r d l di ance from h r ta ing at t e forward end he a th ar end and ha in 18 p nra ityof rad ally e tending en -te bits s nose alo i the out fa e andtowar' th l ad ng edge thereof, whereby said boring. arm'assembly C l bePivot- ,p r do n ela i e to en b 'sewhi cu ng to {0. loyya ie o s in'level f le ani.

No references cited. 

